Standards of admission capillary blood glucose levels in cesarean born neonates

Background:Neonatal hypoglycemia (NH) and cutoffs remain undefined.Our center screens all cesareandelivered (CD) neonates for NH.We sought to define standards of admission capillary blood glucose levels (ACBGLs) in CD neonates who were at the lowest risk for hypoglycemia.Methods:Of 4947 neonates,519 met all 14 inclusion criteria.These highly-selected neonates were apparently the healthiest,least-stressed,earliest to be admitted to nursery and at lowest-risk for hypoglycemia.For each CD,cord blood gases and glucose were determined and each infant was screened for blood glucose at nursery admission.Results:Sampling age was 41.6±15.3 minutes,a mean ACBGL of 52.3±10.7 mg/dL,and percentiles as follows:1st percentile,29.2;3rd,33.6;5th,35.0;10th,39.0;25th,46.0;50th,51.0;75th,58.0;90th,67.0;95th,71.0;97th,73.0,and 99th,84.4.ACBGL rose significantly with increasing gestational age (P=0.004),increasing cord blood glucose (P<0.001),decreasing cord blood pH (P<0.001) and decreasing sampling age (P=4).027).Conclusions:Setting uniform ACBGL cutoffs for NH definition is unachievable due to the enormous heterogeneity among newborns.Hence,we provide group-based ACBGL standards in CD neonates.We propose setting ACBGL cutoffs for use in CD neonates:1) hypoglycemia:ACBGL <5th percentile (<35 mg/dL);and 2) interventional hypoglycemia:ACBGL <1st percentile (<30 mg/dL).

Hyperthyroxinemia at birth: a cause of idiopathic neonatal hyperbilirubinemia?

Background Some neonates develop idiopathic hyperbilirubinemia (INHB) requiring phototherapy, yet with no identifi able causes. We searched for an association between abnormal thyroid levels after birth and INHB. Methods Of 5188 neonates, 1681 (32.4%) were excluded due to one or more risk factors for hyperbilirubinemia. Total thyroxine (TT4) and thyroid stimulating hormone values were sampled routinely at 40-48 hours of age and measured in the National Newborn Screening Program. Results Of the 3507 neonates without known causes for hyperbilirubinemia, 61 (1.7%) developed INHB and received phototherapy. Univariate analyses found no signifi cant association between mode of delivery and INHB (vacuum-delivered neonates were a priori excluded). Nonetheless, in cesarean-delivered (CD) neonates, two variables had signifi cant asso-ciation with INHB: TT4 ≥ 13 μg/dL and birth at 38-38.6 weeks. In vaginally delivered (VD) born neonates, INHB was associated with weight loss > 7.5% up to 48 hours of age. Multivariate logistic regression analysis showed a strong eff ect of mode of delivery on possible signifi cant association with INHB. In CD neonates, such variables included: TT4 ≥ 13 μg/dL [P = 0.025, odds ratio (OR) 5.49, 95% confi dence interval (CI) 1.23-24.4] and birth at 38-38.6 weeks (P = 0.023, OR 3.44, 95% CI 1.19-9.97). In VD neonates, weight loss > 7.5% (P = 0.019, OR 2.1, 95% CI 1.13-3.83) and 1-min Apgar score < 9 (P < 0.001, OR 3.8, 95% CI 1.83-7.9), but not TT4, showed such an association. Conclusions INHB was signifi cantly associated with birth on 38-38.6 week and TT4 (≥ 13 μg/dL) in CD neonates, and with a weight loss > 7.5% in VD neonates. We herein highlight some acknowledged risk factors for neonatal hyperbilirubinemia, and thus minimize the rate of INHB.